Rubber-compounding mixture



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To all whom it may concern:

Be it known that l, Gronen J. Cm'rorr, a citizen of the United States of America, residing at Cleveland, in the county of Guyahoga and State of Ohio, have invented certain new and "useful Improvements 1n Rubber-Compounding Mixtures, of which the following is a specification.

My invention relates to improvements 1n rubber compouding mixture, and has for its object the provision of an iugredlent adapted for use In working or compounding rubher, which is designed materially to improve the completed product. My invention further contemplates the rubber product thus compounded and improved.

it is a matter of common knowledge among rubber manufacturers, that rubber compositions difier widely in their characteristics, but all are subject to more or less rapid deterioration, 'hardenin with age and the blooming ofsulfur. present iIIVIBDtIOD contemplates the deferring or avoidance of these undesirable features, through the production and incorporation of a small percentage of a suitable mixture or mgredient which will supplement the natural caoutchoucin the rubber.

Briefly stated, the improvement consists in efiectmg a suitable non-oxidizing mixture in the presence of heat of a suitable vege table oil and an amorphous omidized hydrocarbon of the resin group. This mixture is worked into the mass of the rubber, preterably during milling and in relatively small percentages as three per cent. or less.

The resulting product will be found to resist the ordinary deteriorating conditlons, much better than when the rubber is worked without my improved mixture. Moreover,

the sticky properties of the rubber, such as that prepared for rubber tape stock, is found tobe greatly enhanced, wlule the sulfur ordinarily is prevented from blOOlIllIlg.

The employment of this mixture also permits the incorporation of desired percentages of cured bufied scrap .for which it acts as a binder, in incorporating the rubber dust upon subsequent vulcanizatlon.

Preferably the ingredients indicated are melted together into homogeneous fluld mixture before their incorporatin into the mass of rubber, although I do not wish to be understood necessarily my inven- Specification of Letters Patent.

' basic mineral content,

Patented May at, rear...

Application filed Hatch 2b, 191%. serial No. 223,684.

tion thereto. However, it should be observed that the addition of dissimilar ingredients other than those indicated may nulli or overcome the beneficial efiect procurab 0 through the use of my mixture.

The specific ingredients are compounded approximately in equal parts by weight of the resinous substance and the vegetable oils employed. Of these, I have used and recommend 'colophony or ordinary resin, dammar resin and copal gum. The preferred oils which I have used are palm oil, resin oil, pine oil and turpentine. lit should be observed that these oils preferred for use herein, are relatively non-oxidizing, nonvolatile and non-drylng. Depending upon temperature conditions largely, the proportlon of oils used in my compounding mixture may vary from 30% to of the total Wei ht. T ese ingredients are mixed by first meltmg the resinous substance and then adding the desired percentage of vegetable oils, usually about fifty per cent. The resulting product is a solution which may most readily be employed in compounding the rubber therewith. lit will This serves to render the abiatic acid content much more active, which upon subjecting the rubber stock thereto,

reacts upon the forming definite chemical compounds, such as calcium resinate. The resultant stock approximates a neutral reaction and the resinate therein is strongly adhesive. These resultsmay be approximated only in a minor degree by treating rubber stock with resin and with oils which have not previously been incorporated by pro-heating.

Dependlng somewhat upon the condition of the rubber stock to be treated, varying percentages of my improved mixtures may be worked into the rubber mass while it is being milled; such percentages ranging from one to three per cent. only, as compared with the rubber stock. After the compounded rubber has been curedin the mannor desired, its properties will be found to have been materially enhanced in the mam be understood that any Increase of the percentage of vegetable oil til (til) Mid ner already indicated, thereby economically obtaining a much more deslrable product than otherwise might be secured.

Having now described the referred mode of practising my invention, claim as new, and desire to secure by Letters Patent, the following i 1. A fluid rubber-compounding mixture, consisting of a resinous substance and a relatively non-volatile solvent incorporated in the presence of heat, substantially as set forth. 7

2. A fluid rubber-compounding mixture, consisting of a resinous substance and a relatively non-oxidizing, non-drying vegetable I 'cured bufl'ed scrap vulcanized with a resinoil incorporated in the presence'of heat, substantially as set forth.

3. A fluid rubber-compounding mixture, consisting of a resin, pine, and palm oil incorporated in the presence of heat, to effect solution, fluid at normal temperatures, substantially as set forth.

4. A fluid rubber-compounding mixture, consisting of a resinous substance and a relatively non-oxidizing vegetable oil incorporated in the presence of heat holding the same in solution, and approximating equal proportions by weight, substantially as set orth.

vegetable oil pr'e-heated together, these-aggregating not to exceed three per cent; of the rubber stock, substantially as set forth. 7. A composition containing rubber and ous substance and a vegetable oil pre-heated together and constituting less than two percent of the stock treated, substantially as set forth. I

In testimon whereof I do now aifix my signature in t e resence of two witnesses.

GE RGE J .CHERTOFF.

Witnesses: I GLADYS FORREST, ALBERT LYNN LAWRENCE. 

